修复：CI 部署环境与 ref 错配、迁移碎片化、图片意图 source_span、章节物化脏版式、会话历史与本地语音不一致

新增：TTS 上传 COS 与分片、章节 reading_segments 物化与快照、markdown 清洗、会话消息 repository、语音 store 重构与相关测试

api/app/features/memoir/markdown_sanitize.py

@@ -0,0 +1,63 @@
+"""章节物化前对 story 正文的受限清洗：禁止表格、可选剥离与标题元数据重复的首行 heading。"""
+
+from __future__ import annotations
+
+import re
+
+
+def _is_table_row(line: str) -> bool:
+    s = line.strip()
+    if not s.startswith("|"):
+        return False
+    return s.count("|") >= 2
+
+
+def strip_markdown_tables(text: str) -> str:
+    """移除 GFM 管道表格块（连续以 | 开头的行）。"""
+    if not text or not str(text).strip():
+        return ""
+    lines = str(text).splitlines()
+    out: list[str] = []
+    i = 0
+    while i < len(lines):
+        if _is_table_row(lines[i]):
+            while i < len(lines) and _is_table_row(lines[i]):
+                i += 1
+            continue
+        out.append(lines[i])
+        i += 1
+    return "\n".join(out).strip()
+
+
+_HEADING_LINE_RE = re.compile(r"^#{1,6}\s+(.+?)\s*$")
+
+
+def _normalize_title_key(s: str) -> str:
+    return "".join((s or "").split()).casefold()
+
+
+def strip_leading_heading_if_matches_title(body: str, story_title: str) -> str:
+    """若首行为 markdown 标题且与 story 标题（规范化后）一致，则移除该行。"""
+    if not body or not str(body).strip():
+        return body or ""
+    st_key = _normalize_title_key(story_title or "")
+    if not st_key:
+        return body
+    lines = str(body).splitlines()
+    if not lines:
+        return body
+    m = _HEADING_LINE_RE.match(lines[0].strip())
+    if not m:
+        return body
+    heading_key = _normalize_title_key(m.group(1))
+    if heading_key != st_key:
+        return body
+    rest = "\n".join(lines[1:])
+    return rest.lstrip("\n")
+
+
+def sanitize_story_for_chapter_compose(body: str, story_title: str) -> str:
+    """物化章节前：去表格、去与元数据重复的首行标题。"""
+    t = strip_markdown_tables(body or "")
+    t = strip_leading_heading_if_matches_title(t, story_title)
+    return (t or "").strip()